process: add --redirect-warnings command line argument · nodejs/node@03e89b3 · GitHub
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process: add --redirect-warnings command line argument
The --redirect-warnings command line argument allows process warnings to be written to a specified file rather than printed to stderr. Also adds an equivalent NODE_REDIRECT_WARNINGS environment variable. If the specified file cannot be opened or written to for any reason, the argument is ignored and the warning is printed to stderr. If the file already exists, it will be appended to. PR-URL: #10116 Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com> Reviewed-By: Michal Zasso <targos@protonmail.com> Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>
1 parent 5e1f32f commit 03e89b3

8 files changed

Lines changed: 186 additions & 6 deletions

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‎doc/api/cli.md‎

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‎doc/node.1‎

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@@ -112,6 +112,10 @@ Silence all process warnings (including deprecations).
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.BR \-\-trace\-warnings
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Print stack traces for process warnings (including deprecations).
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.TP
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.BR \-\-redirect\-warnings=\fIfile\fR
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Write process warnings to the given file instead of printing to stderr.
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.TP
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.BR \-\-trace\-sync\-io
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Print a stack trace whenever synchronous I/O is detected after the first turn
@@ -262,6 +266,12 @@ containing trusted certificates.
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If \fB\-\-use\-openssl\-ca\fR is enabled, this overrides and sets OpenSSL's
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file containing trusted certificates.
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.TP
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.BR NODE_REDIRECT_WARNINGS=\fIfile\fR
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Write process warnings to the given file instead of printing to stderr.
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(equivalent to using the \-\-redirect\-warnings=\fIfile\fR command-line
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argument).
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.SH BUGS
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Bugs are tracked in GitHub Issues:
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.ur https://github.com/nodejs/node/issues

‎lib/internal/process/warning.js‎

Lines changed: 76 additions & 6 deletions
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@@ -1,9 +1,80 @@
11
'use strict';
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const config = process.binding('config');
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const prefix = `(${process.release.name}:${process.pid}) `;
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exports.setup = setupProcessWarnings;
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var fs;
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var cachedFd;
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var acquiringFd = false;
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function nop() {}
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function lazyFs() {
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if (!fs)
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fs = require('fs');
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return fs;
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}
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function writeOut(message) {
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if (console && typeof console.error === 'function')
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return console.error(message);
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process._rawDebug(message);
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}
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function onClose(fd) {
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return function() {
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lazyFs().close(fd, nop);
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};
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}
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function onOpen(cb) {
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return function(err, fd) {
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acquiringFd = false;
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if (fd !== undefined) {
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cachedFd = fd;
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process.on('exit', onClose(fd));
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}
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cb(err, fd);
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process.emit('_node_warning_fd_acquired', err, fd);
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};
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}
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function onAcquired(message) {
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// make a best effort attempt at writing the message
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// to the fd. Errors are ignored at this point.
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return function(err, fd) {
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if (err)
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return writeOut(message);
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lazyFs().appendFile(fd, `${message}\n`, nop);
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};
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}
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function acquireFd(cb) {
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if (cachedFd === undefined && !acquiringFd) {
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acquiringFd = true;
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lazyFs().open(config.warningFile, 'a', onOpen(cb));
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} else if (cachedFd !== undefined && !acquiringFd) {
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cb(null, cachedFd);
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} else {
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process.once('_node_warning_fd_acquired', cb);
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}
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}
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function output(message) {
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if (typeof config.warningFile === 'string') {
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acquireFd(onAcquired(message));
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return;
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}
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writeOut(message);
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}
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function doEmitWarning(warning) {
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return function() {
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process.emit('warning', warning);
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};
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}
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function setupProcessWarnings() {
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if (!process.noProcessWarnings && process.env.NODE_NO_WARNINGS !== '1') {
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process.on('warning', (warning) => {
@@ -14,19 +85,18 @@ function setupProcessWarnings() {
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(isDeprecation && process.traceDeprecation);
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if (trace && warning.stack) {
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if (warning.code) {
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console.error(`${prefix}[${warning.code}] ${warning.stack}`);
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output(`${prefix}[${warning.code}] ${warning.stack}`);
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} else {
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console.error(`${prefix}${warning.stack}`);
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output(`${prefix}${warning.stack}`);
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}
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} else {
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const toString =
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typeof warning.toString === 'function' ?
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warning.toString : Error.prototype.toString;
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if (warning.code) {
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console.error(
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`${prefix}[${warning.code}] ${toString.apply(warning)}`);
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output(`${prefix}[${warning.code}] ${toString.apply(warning)}`);
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} else {
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console.error(`${prefix}${toString.apply(warning)}`);
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output(`${prefix}${toString.apply(warning)}`);
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}
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}
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});
@@ -63,6 +133,6 @@ function setupProcessWarnings() {
63133
if (process.throwDeprecation)
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throw warning;
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}
66-
process.nextTick(() => process.emit('warning', warning));
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process.nextTick(doEmitWarning(warning));
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};
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}

‎src/node.cc‎

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Original file line numberDiff line numberDiff line change
@@ -188,6 +188,9 @@ bool trace_warnings = false;
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// that is used by lib/module.js
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bool config_preserve_symlinks = false;
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// Set in node.cc by ParseArgs when --redirect-warnings= is used.
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const char* config_warning_file;
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191194
bool v8_initialized = false;
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// process-relative uptime base, initialized at start-up
@@ -3499,6 +3502,9 @@ static void PrintHelp() {
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" --throw-deprecation throw an exception on deprecations\n"
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" --no-warnings silence all process warnings\n"
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" --trace-warnings show stack traces on process warnings\n"
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" --redirect-warnings=path\n"
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" write warnings to path instead of\n"
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" stderr\n"
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" --trace-sync-io show stack trace when use of sync IO\n"
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" is detected after the first tick\n"
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" --trace-events-enabled track trace events\n"
@@ -3564,6 +3570,8 @@ static void PrintHelp() {
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" prefixed to the module search path\n"
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"NODE_REPL_HISTORY path to the persistent REPL history\n"
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" file\n"
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"NODE_REDIRECT_WARNINGS write warnings to path instead of\n"
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" stderr\n"
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"Documentation can be found at https://nodejs.org/\n");
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}
35693577

@@ -3664,6 +3672,8 @@ static void ParseArgs(int* argc,
36643672
no_process_warnings = true;
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} else if (strcmp(arg, "--trace-warnings") == 0) {
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trace_warnings = true;
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} else if (strncmp(arg, "--redirect-warnings=", 20) == 0) {
3676+
config_warning_file = arg + 20;
36673677
} else if (strcmp(arg, "--trace-deprecation") == 0) {
36683678
trace_deprecation = true;
36693679
} else if (strcmp(arg, "--trace-sync-io") == 0) {
@@ -4206,6 +4216,10 @@ void Init(int* argc,
42064216
config_preserve_symlinks = (*preserve_symlinks == '1');
42074217
}
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4219+
if (auto redirect_warnings = secure_getenv("NODE_REDIRECT_WARNINGS")) {
4220+
config_warning_file = redirect_warnings;
4221+
}
4222+
42094223
// Parse a few arguments which are specific to Node.
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int v8_argc;
42114225
const char** v8_argv;

‎src/node_config.cc‎

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Original file line numberDiff line numberDiff line change
@@ -12,6 +12,7 @@ using v8::Context;
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using v8::Local;
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using v8::Object;
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using v8::ReadOnly;
15+
using v8::String;
1516
using v8::Value;
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1718
// The config binding is used to provide an internal view of compile or runtime
@@ -44,6 +45,15 @@ void InitConfig(Local<Object> target,
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4546
if (config_preserve_symlinks)
4647
READONLY_BOOLEAN_PROPERTY("preserveSymlinks");
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49+
if (config_warning_file != nullptr) {
50+
Local<String> name = OneByteString(env->isolate(), "warningFile");
51+
Local<String> value = String::NewFromUtf8(env->isolate(),
52+
config_warning_file,
53+
v8::NewStringType::kNormal)
54+
.ToLocalChecked();
55+
target->DefineOwnProperty(env->context(), name, value).FromJust();
56+
}
4757
} // InitConfig
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4959
} // namespace node

‎src/node_internals.h‎

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@@ -42,6 +42,11 @@ extern const char* openssl_config;
4242
// that is used by lib/module.js
4343
extern bool config_preserve_symlinks;
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45+
// Set in node.cc by ParseArgs when --redirect-warnings= is used.
46+
// Used to redirect warning output to a file rather than sending
47+
// it to stderr.
48+
extern const char* config_warning_file;
49+
4550
// Tells whether it is safe to call v8::Isolate::GetCurrent().
4651
extern bool v8_initialized;
4752

‎test/parallel/test-process-redirect-warnings-env.js‎

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,25 @@
1+
'use strict';
2+
3+
// Tests the NODE_REDIRECT_WARNINGS environment variable by spawning
4+
// a new child node process that emits a warning into a temporary
5+
// warnings file. Once the process completes, the warning file is
6+
// opened and the contents are validated
7+
8+
const common = require('../common');
9+
const fs = require('fs');
10+
const fork = require('child_process').fork;
11+
const path = require('path');
12+
const assert = require('assert');
13+
14+
common.refreshTmpDir();
15+
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const warnmod = require.resolve(common.fixturesDir + '/warnings.js');
17+
const warnpath = path.join(common.tmpDir, 'warnings.txt');
18+
19+
fork(warnmod, {env: {NODE_REDIRECT_WARNINGS: warnpath}})
20+
.on('exit', common.mustCall(() => {
21+
fs.readFile(warnpath, 'utf8', common.mustCall((err, data) => {
22+
assert.ifError(err);
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assert(/\(node:\d+\) Warning: a bad practice warning/.test(data));
24+
}));
25+
}));

‎test/parallel/test-process-redirect-warnings.js‎

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